ArcObjects Library Reference (GeoAnalyst)  

ISurfaceOp2.HillShade Method

Calculates Hillshade.

[Visual Basic .NET]
Public Function HillShade ( _
    ByVal GeoDataset As IGeoDataset, _
    ByVal azimuth As Double, _
    ByVal altitude As Double, _
    ByVal inModelShadows As Boolean, _
    [ByRef zFactor As Object] _
) As IGeoDataset
[C#]
public IGeoDataset HillShade (
    IGeoDataset GeoDataset,
    double azimuth,
    double altitude,
    bool inModelShadows,
    ref object zFactor
);
[C#]

Optional Values

zFactor   To indicate that this parameter is undefined, first define a variable object Missing = Type.Missing; then pass this in as ref Missing.
[C++]
HRESULT HillShade(
  IGeoDataset* GeoDataset,
  double azimuth,
  double altitude,
  VARIANT_BOOL inModelShadows,
  VARIANT* zFactor,
  IGeoDataset** outGeoDataset
);
[C++]

Parameters

GeoDataset [in]

  GeoDataset is a parameter of type IGeoDataset

azimuth [in]
  azimuth is a parameter of type double
altitude [in]
  altitude is a parameter of type double
inModelShadows [in]
  inModelShadows is a parameter of type VARIANT_BOOL
zFactor [optional]
  zFactor is a parameter of type VARIANT

  To indicate this parameter is undefined pass a reference to a VARIANT with type VT_ERROR and scode value of DISP_E_PARAMNOTFOUND.

outGeoDataset [out, retval]

  outGeoDataset is a parameter of type IGeoDataset

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Remarks

geoDataset

the input Raster, RasterDataset, RasterBand, or RasterDescriptor from which the shaded relief is derived

azimuth

the azimuth angle of the light source. The azimuth is expressed in positive degrees from 0 to 360, measured clockwise from the north. A commonly used azimuth is 315 degrees

altitude

the slope or angle of the illumination source above the horizon. The slope is expressed in positive degrees, with 0 degrees at the horizon and 90 degrees directly overhead. A commonly used altitude is 45 degrees

inModelShadows

a Boolean specifying the type of shaded relief to be generated

If True, the output shaded relief Raster will consider both local illumination angles and shadows. The output Raster contains values ranging from 0 and 255, with 0 representing the areas in shadow, and 255 the brightest.

If False, the output shaded relief Raster only considers local illumination angles; the effects of shadows are not considered. The output grid contains values ranging from 0 and 255, with 0 representing the darkest areas and 255 the brightest.

[zFactor]

the geoDataset ZUnits are multiplied by the specified [zFactor] to adjust the output Raster ZUnits to another unit of measure. If no [zFactor] is specified, a [zFactor] of 1 is applied. Higher z values will result in a more exaggerated relief (surface) and thus in a more extreme shading

 

See Also

ISurfaceOp2 Interface